AAT1126 AAT, AAT1126 Datasheet
AAT1126
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AAT1126 Summary of contents
Page 1
... AAT1126 the ideal choice for portable applications. The AAT1126 is available in either a fixed version with internal feedback or a programmable version with external feedback resistors. It can deliver up to 600mA of load current while maintaining a low 25µ ...
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... Feedback input pin. This pin is connected either directly to the converter output external resistive divider for an adjustable output. 5 VIN Input supply voltage for the converter. Pin Configuration 2 600mA, 1MHz Step-Down Converter SOT23-5 (Top View) GND VIN OUT 3 4 AAT1126 1126.2006.05.1.1 ...
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... Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condi- tions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time. 2. Mounted on an FR4 board. 1126.2006.05.1.1 600mA, 1MHz Step-Down Converter 1 ( SOT23-5) 2 AAT1126 Value Units 6 ...
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... Enable Threshold Low EN(L) V Enable Threshold High EN(H) I Input Low Current EN 1. The AAT1126 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and correlation with statistical process controls. 4 600mA, 1MHz Step-Down Converter 1 = 25° Conditions ...
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... V = 3.9V IN 1.0 0.0 -1.0 V -2.0 -3.0 0.1 100 1000 3 2.0 1.0 0.0 V -1.0 -2.0 -3.0 100 1000 0.1 3.0 V 2.0 1.0 0.0 V -1.0 -2.0 -3.0 100 1000 0.1 AAT1126 DC Regulation = 3.3V 10μ μ OUT 100 Output Current (mA) DC Regulation = 2.5V 10μ μ OUT = 100 Output Current (mA) DC Regulation = 1.5V 4.7μ μ OUT = 4. 3. 2.7V IN ...
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... Quiescent Current vs. Input Voltage 2 100 N-Channel R 750 700 650 600 550 500 450 400 25°C 350 300 5.0 5.5 6.0 2.5 AAT1126 (V = 3.6V 2.5V - Temperature (° ° 1.8V) O 85°C 25°C -40°C 3.0 3.5 4.0 4.5 5.0 5.5 Input Voltage (V) vs. Input Voltage DS(ON) 120°C 100° ...
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... Step-Down Converter Load Transient Response (30mA - 300mA; V 2.65 1.5 2.55 1.3 1.1 2.45 0.9 2.35 0.7 0.5 2.25 0.3 2.15 0.1 -0.1 2.05 Time (25μs/div) 2 7.0 6.5 1.5 6 OUT 5.5 0.5 5.0 4.5 0 4.0 -0.5 3.5 -1 3.0 2 3.6V 4.0 0.9 3.0 0.8 2.0 0.7 1.0 0.6 0.0 0.5 -1.0 0.4 -2.0 0.3 -3.0 0.2 -4.0 0.1 Time (50μs/div) AAT1126 = 2.5V 22μ μ 3.6V OUT 1.5 1.3 1.1 300mA 0.9 30mA 0.7 0.5 0.3 0.1 -0.1 Line Regulation (V = 1.5V) OUT = 600mA I = 100mA OUT I = 10mA OUT 4 4.5 5 5.5 6 Input Voltage (V) Soft Start = 1.5V 4.7μ μ H) OUT 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 -0.5 7 ...
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... Note: For adjustable version, the internal feedback divider is omitted and the OUT pin is tied directly to the internal error amplifier. Functional Description The AAT1126 is a high performance 600mA 1MHz monolithic step-down converter. It has been designed with the goal of minimizing external com- ponent size and optimizing efficiency over the com- plete load range ...
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... GND Figure 1: Enhanced Transient Response Schematic. Control Loop The AAT1126 is a peak current mode step-down converter. The current through the P-channel MOSFET (high side) is sensed for current loop control, as well as short circuit and overload pro- tection. A fixed slope compensation signal is added to the sensed current to maintain stability for duty cycles greater than 50% ...
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... The internal slope compensation for the adjustable and low-voltage fixed versions of the AAT1126 is 0.24A/µsec. This equates to a slope compensation that is 75% of the inductor current down slope for a 1.5V output and 4.7µH inductor. 0.75 ⋅ V 0.75 ⋅ ...
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... The input capacitor provides a low impedance loop for the edges of pulsed current drawn by the AAT1126. Low ESR/ESL X7R and X5R ceramic capacitors are ideal for this function. To minimize stray inductance, the capacitor should be placed 1 as closely as possible to the IC ...
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... R2 set to either 59kΩ for good noise immunity or 221kΩ for reduced no load input current. ⎛ ⎝ The adjustable version of the AAT1126, combined with an external feedforward capacitor (C4 in Figure 1), delivers enhanced transient response for S extreme pulsed load applications. The addition of the feedforward capacitor typically requires a larg- er output capacitor C1 for stability ...
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... JP1 Enable V OUT C1 10µF GND Figure 5: AAT1126 Adjustable Evaluation Board Schematic. 1126.2006.05.1.1 600mA, 1MHz Step-Down Converter Conduction losses are associated with the 221kΩ Ω characteristics of the power output switching R1 (kΩ Ω ) devices. Switching losses are dominated by the gate charge of the power output switching devices ...
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... J(MAX) TOTAL JA Layout The suggested PCB layout for the AAT1126 is shown in Figures 2, 3, and 4. The following guide- lines should be used to help ensure a proper layout. 14 600mA, 1MHz Step-Down Converter 1. The input capacitor (C2) should connect as close possible and L1 should be connected as closely as possible ...
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... L1 · F · · 3 IN(MAX esr · 5mΩ · (63mA) esr RMS 1126.2006.05.1.1 600mA, 1MHz Step-Down Converter (see Table 1) ⎛ ⎞ 1.8V ⋅ 218mA ⎝ ⎠ 4.2V = 18.0μF 1 1.8V · (4.2V - 1.8V) · = 63mArms = 4.7μH · 1.0MHz · 4.2V 2 · 20μW AAT1126 = 300mA LOAD 15 ...
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... PP - ESR · 4 · F ⎝ ⎠ ⎝ 0. 0.2Arms RMS esr · 5mΩ · (0.2A) = 0.2mW RMS AAT1126 Losses 2 I · (R · DSON(HS) O DSON(LS TOTAL · F · · · (0.45 Ω · 1.8V + 0.4Ω · [4.2V - 1.8V ...
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... R1 (kΩ Ω Not Used 0 Inductance Max DC (µH) Current (A) 4.7 0.90 10 0.84 4.7 0.65 4.7 0.65 4.7 1.10 4.7 0.80 4.7 1.53 4.7 1.30 4.7 0.98 4.7 1.77 AAT1126 L1 (µ 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4 (µH) 4.7 DCR Size (mm) (Ω Ω ) LxWxH Type 0.11 4.0x4.0x1.8 Shielded 0.23 4.0x4.0x1.8 Shielded 0.15 2.5x3.2x2.0 Non-Shielded 0.15 2.5x3.2x1.55 Non-Shielded 0.20 5.5x6.6x1.0 1mm 0 ...
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... Manufacturer Part Number MuRata GRM21BR60J226ME39 MuRata GRM21BR60J106KE19 18 600mA, 1MHz Step-Down Converter Value 22µF 10µF Table 5: Surface Mount Capacitors. AAT1126 Voltage Temp. Co. Case 6.3V X5R 0805 6.3V X5R 0805 1126.2006.05.1.1 ...
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... Contact Sales for other voltage options. 2. XYY = assembly and date code. 3. Sample stock is generally held on part numbers listed in BOLD. 1126.2006.05.1.1 600mA, 1MHz Step-Down Converter Marking 2 SOT23-5 QPXYY SOT23-5 0.075 ± 0.075 0.60 REF AAT1126 Part Number (Tape and Reel) 3 AAT1126IGV-0.6-T1 0.15 ± 0.07 GAUGE PLANE 0.45 ± 0.15 0.10 BSC 19 ...
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... AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are regis- tered trademarks or trademarks of their respective holders. Advanced Analogic Technologies, Inc. 830 E. Arques Avenue, Sunnyvale, CA 94085 Phone (408) 737-4600 Fax (408) 737-4611 20 600mA, 1MHz Step-Down Converter AAT1126 1126.2006.05.1.1 ...